s=input("Input your age:")
if s =="":
    raise Exception("Input must no be empty.")
try:
    i=int(s)
except ValueError:
    print("Could not convert data to an integer.")
except:
    print("Unknown exception!")
else: # It is useful for code that must be executed if the try clause does not raise an exception
    print("You are %d" % i," years old")
finally: # Clean up action
    print("Goodbye!")
